Automatic carburetor



Dec. 28, 1926. 1,612,597 A. M. ALEXANDRESCU AUTOMATI C CARBURETOR Filed Nov. 5. 1924 2 Sheets-Sheet 1 IMF, S. I 33 I w'm- M 1" y 23 9- If Dec. 28,1926.

i I 1,612,597 A M. ALEXANDRESCU AUTOMATIC CARBURETOR Filed Nov. 5, 1924 2 SneeL's-Sheet 2 Patented 28, 1926.

' UNITED T'STATES ALEXANDER I. ALEXANDBESGU, OF CLEVELAND, OHIO.

AUTOMATIC CARBURETOR.

Application filed November 5, 1924. Serial No. 747,945.

The present invention relates to improvements in automat c carburetors and hasfor I an object to provide a carburetor havin controls for producing a mixture suscepti le of being regulated to extremely fine proportions of air and fuel and to accomplish this result by a. mechanism that is automatic and hereto.

. level b the 'use of the float device indicated reliable in operation.

Other objects of the invention are to provide improvements in the control of the air inlet; of the fuel nozzle and to provide a by-pass extending about the nozzle and throttle for the air whereby to automatically dilute the mixture in the manifold and to further serve the purpose at relieving the vacuum in the cylinders when the throttle is closed thus preventing oil from the crank case from being drawn up into the cylinder heads fouling'the spark plugs, creating carbon deposits, reducing the power of the motor and producing obnoxious smoke at the exhaust pipe.

With the foregoing and other objects in view, the invention will be more fully described hereinafter, and will be more particularly pointed outin the claims appended In the drawings, wherein like symbols refer to like or corresponding parts throughout the several views, v

' Figure 1 is a top plan view of an improved automatic carburetor constructed according to the invention.

Figure 2 is a vertical section taken on the line 22 in Figure 1. I

Figure 3 is a horizontal section taken on the line 3-3 in Figure 2.

Figure 4 is an end view.

Figure 5 is also an end view from the opposite end of the carburetor and with certain parts broken away. v

Figure 6'is'a vertical section taken on the line6-6in Figure 4;

Figure 7 is a fragmentary side view showing the air inlet valve control, and

Figure 8,. is a fragmentary sectional view showing on an enlarged scale a portion of the b -pass and its control valve.

Re erring more particularly to the drawings the improved carburetor is composed of a shell or casing havin in the lowercentral portion thereof the'fue chamber 9 in which theliquid fuel is maintained at constant at 10, ut which is not illustrated in detail as this float device is of well known constiuction. At 11 is indicated the inlet for the asoline or other liquid fuel to the cham er 9.

The chamber 9 is shown as a cup shaped reservoir having anopenupper end secured against the shoulder 12 of the main carburetor shell. This main carburetor shell is formed with a nozzle post 13 having the internal bore 14 and the nozzle 15 fitting in the bore and being of smaller diameter than said bore whereby to provide a chamber about the nozzle for the circulation of air, which air is received through the perforation 16 in one side of the post, the post being provided with the duct '17 at its side communicating with the port 16. The duct 17 opens at its upper en upon the bypass 18. The bypass is-shown -in .Figure 2 and includes the portion 18 which extends substantially horizontally, the vertical portion-19 which conimunicates with the inner end of the portion 18 and also opens at its lower end upon the float chamber 9 so as to receivethe vapor therefrom. The by-..pass further includes the second .horizontal branch or ortion 20 connecting with the upper part 0 the vertical intermediate portion 19. The outer ends of the passages 18 and 20 are closed by the clean-out plugs 21 and 22respectively and adjacent its plugs are the ports 23 and 24,

also showing in Figure 6.

The intermediate ortion 19 of the bypass is formed of di erential diameters producing a shoulder and valve seat against the edge of which the conical valve26 is adapted to close. This valve is provided just above with the head orflange comprising a number of radial fingers 25 se arated a distance apart and acting as a gui e for the valve to slide in the upper larger portion of the vertical part 19. The valve and head are carried upon the lower end of the stem 27 and the coil spring 28, wound about the stem is made use of to retain the valve in the closed position. It will also seek this ,position by gravity. An adjustment of the spring may be made through the hollow' same. This butterfly valve 'is v arranged in the mixture passage 32 which connects with the manifold. The intake port 23 'for the by-pass enters the passage 33 on the atmospheric side of the choke valve while the outlet port 24- of the by-pass enters the air passage 32 on the manifold of the throttle valve 31; Theair inlet passage 33 and the mixture or carbureting passage 32 are in substantially horizontal alinement, and at their meeting point are intersected by the fuel nozzle 15. The fuel control valve is represented at and may be screwed up'or down toward or from the nozzle. The internal .wall of the carburetor is shaped to direct the incoming air downwardly toward the nozzle and the air valve 34 is pivoted above the passage 33 and opens inwardly to a dittgonal own- ' position to further deflect the air wardly upon the nozzle. The air valve 34'is provided at its upper end with the tubular casing 36 fitting loosely about the control shaft 37 The shaft is provided with a set screw 38 extending therefrom and through the arcuate slot 39 of the casin 36. In Figure 7 the shaft 37 is s own to project beyond the wall of the air passage and to be provided with the bell crank lever 40 held in the lower portion yeildili'gly by a 'coil spring 41. In this position the lug 42 of the bell crank lever engages the stop 43 on the casing. This is-the condition of part shown in Figure 6, the set screw 38 being in an upper position and permitting the air valve 34 to be swung inwardly thro gngular movement equal to the circum erenlength of the slot 39. As a consequence greater suction in the motor will draw reater quantities of air through the air intake and the valve 34 may swing open to accommodate the maximum draft. The air intake may or may not bev connected with a hot air source or with a device for preheatin the air. The throttle valve operating device is indicated at 44 in Figure 1.

In the use of the device, the engine is started, by pulling out the choke on the dash board. This choke is connected to the bell crank lever 40 and the air or choke valve 34 is closed when the choke pull rod is fully drawn out from the dash or instrument board. By drawing this pull rod outthe bell crank lever 40 is rotated in a clockwise direction (see Figure 7) and the shaft and set screw 38 are made to move through the slot 39 and a ainst the lower wallof said slot pushing t e casing and air valve around until in the extreme left dotted linefposition shown in- Figure 6, where the valve closes against the bottom wall of the air p andv no air is permitted to be drawn into the engine. The throttle valve 31 is opened generally to a rather wide extent and the starter is put in operation causing the motor pistons to move up and down and create the inrushes of air.

will pass across the nozzle and pick up fuel h an.

suction. This suction operates draw air in through the by-pass inlet port 23 but the air cannotpass completely through the bypass because the valve 26 1s closed. The air then descends through the duct 17 and enter ing through the port 17 gets into the annular passage at the base of the, nozzle 15. This air ascends and picks up the fuel from the nozzle passing on to the mixing nozzle 15 and to the intake manifold.

motor and the motor gains momentum, a

substantial suction is created which suction thus efiected- After the motor has been sufliciently warmed,,the choke control device is pushed in and the spring 41 will return the As soon as this ,mixture ignites in the fuel is shaft' and the set screw 38 to'the upper position shown in Figure 6 leaving theclioke or air valve 34 free to swing backwardly under The air thus admitted with which it will afterwards become'thoroughl commingled in the mixing passage and t e manifold. Adiluti0n of this mixture will take place to a more or less extent and automatically by the air admitted through the by-pass. I

When the'throttle valveis closed preparatory to stopping, the suction in the cylinders is still present without being relieved b the enterin fuel mixture and consequent y a great difliculty with the present operation of motor vehicles is the fact that at this time oil is drawn from the crank case-up past the pistons in the cylinder head where the oilfouls the plugs, creates carbon deposits and causes smo exhausts. This suction is however relieve by the airwwhich is freely admitted through the by-pass and which thus takes up this suction and prevents it from devolving upon the crank case.-

The improved carburetorwill befo nd.

to efiect a considerable saving in gaso he and to afford quick starting.

It is obvious that various changes and modifications may be made in the details of construction and des' of the above specifi c'ally described embodiment of this 1nven-' tion without departing from the spirit thereof, such chan es and modifications being restricted only y the scope of the following claims. v

What is claimed is:-'

1. A carburetor comprising a hav- III 'bureting passages communicating with one 7 another, a fuel nozzle connecting with the I said'air valve for pivotal movement, a loose chamber and with said passages, an air valve in said air passage, a shaft for supporting connection between said shaft and valve acting as a stop tohold said Valve closed in one position of the parts and permit similar movement of said valve in other positions, and means vfor rotating said shaft to close and permit opening of the valve.

2. A carburetor compris ng a casing having a fuel chamber and connecting air intake and carbureting passages, a throttle valve in the carbureting passa e, an air valve piv otally -mounted in sai air passage .and adapted to deflect the air downwardly, a nozzle connecting with the fuel chamber and wit}? said. passages, and operatihg means having a loose play connection with said air valve for maintaining the same open to a predetermined extent and permitting the -free further; opening of the air valve by increased suctlon in said intake passage.

ALEXANDER M. ALEXANDRESCU. 

